Correction: An earlier version of this op-ed incorrectly referred to the internment of Japanese citizens during World War II. Both U.S. citizens and noncitizens of Japanese descent were interned. This version has been corrected.

Opinion writer

Why such vehemence among Republican leaders in their condemnations of Donald Trump for questioning the objectivity of a federal judge based on his “Mexican heritage”?

This is, in House Speaker Paul D. Ryan’s words, “the textbook definition of a racist comment.” But it is not materially more bigoted than the central premise of Trump’s campaign: that foreigners and outsiders are exploiting, infiltrating and adulterating the real America. How is attacking the impartiality of a judge worse than characterizing undocumented Mexicans as invading predators intent on raping American women? Or pledging to keep all Muslim migrants out of the country? Or citing the internment of U.S. citizens and noncitizens of Japanese descent during World War II as positive precedent?

Is Trump himself a racist? Who the bloody hell cares? There is no difference in public influence between a politician who is a racist and one who appeals to racist sentiments with racist arguments. The harm to the country — measured in division and fear — is the same, whatever the inner workings of Trump’s heart.

No, Trump’s attack on Judge Gonzalo Curiel was not different in kind. But for Republican leaders, this much was new: Since Trump now owns them, they now own his prejudice. Sure, Trump has gone nativist before, but this time it followed their overall stamp of approval, given in the cause of Republican unity. Trump must have known his attack on Curiel would humiliate the GOP leaders who have endorsed him, and he did it anyway. Trump is taking away the option of wishful thinking. Republicans have clung to the hope that Trump might find unsuspected resources of leadership; lacking that, to the hope that he might be co-opted; and lacking that, to the hope of laying low and avoiding the Trump taint. All delusions. Having tied themselves to Trump’s anchor, the protests of GOP leaders are merely the last string of bubbles escaping from their lungs.

So what were senior Republicans thinking when they endorsed Trump? I don’t want to underestimate the difficulties involved in opposing one’s own presumptive nominee. There is tremendous political pressure to be loyal to the team. The arguments against doing anything that might help Hillary Clinton are strong. “This is about moving our agenda forward,” said Ryan in justifying his Trump endorsement.

On May 27, presumptive Republican nominee Donald Trump went on an 11-minute rant about Gonzalo Curiel, the federal judge overseeing several Trump University cases. (Reuters)

Republican leaders, in other words, thought they were in a normal political moment — a time for pragmatism, give-and-take, holding your nose and eventually getting past an unpleasant chore.

But it is not a normal political moment. It is one of those rare times — like the repudiation of Joe McCarthy, or consideration of the Civil Rights Act of 1964, or the Watergate crisis — when the spotlight of history stops on a single decision, and a whole political career is remembered in a single pose. The test here: Can you support, for pragmatic reasons, a presidential candidate who purposely and consistently appeals to racism?

When the choice came, only a handful of Republicans at the national level answered with a firm “no.” A handful. It was not shocking to me that the plurality of an angry Republican primary electorate — grown distrustful of establishment leaders — might choose a populist who appeals to racial prejudice. It is shocking to me — and depressing and infuriating — that almost no elected Republicans of national standing would stand up to it.

By this standard, Sen. Ben Sasse (Neb.) is the moral leader of the GOP. But given the thinness of his company, many of us will never be able to think about the Republican Party in quite the same way again. It still carries many of the ideological convictions I share. Collectively, however, it has failed one of the most basic tests of public justice: Don’t support racists — or candidates who appeal to racism — for public office. If this commitment is not a primary, non-negotiable element of Republican identity, then the party of Lincoln is dead.

Without a passion for universal human dignity and worth — the commitment to a common good in which the powerless are valued — politics is a spoils system for the winners. It degenerates into a way for one group to gain advantage over another. And for Trump in particular, politics seems to be a way for white voters to take back social power following the age of Obama.

Many Republicans, I suspect, will sicken of defending this shabby enterprise — as Sens. Lindsey Graham, Jeff Flake and Mark Kirk have done. The process of unendorsing Trump is humiliating, but only for a moment. The honor of choosing rightly, when it mattered most, will endure.

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House Speaker Paul Ryan (R-Wis.) criticized Donald Trump June 7, for remarks Trump made about a Latino federal judge. However, Ryan said Trump is still a better alternative to Democratic presidential candidate Hillary Clinton. (Reuters)